Mineral Carbonation for Carbon Utilization in Microalgae Culture

Abstract

This paper presents a study on the combination of mineral carbonation with biomass production. Laboratory experiments were performed to investigate the growth of freshwater green microalgae Scenedesmus obliquus in the presence of dissolving mineral carbonates, such as nahcolite (NaHCO3) and nesquehonite (MgCO3·3H2O) at atmospheric conditions and 25 °C. The cell density of the algae biomass was determined using fluorescence measurements. A biochemical model was implemented to describe the evolution of the biomass and the consumption of carbon substrate. The parameter estimates show that the algae growth kinetics in the presence of either NaHCO3 or MgCO3·3H2O is similar and is comparable to the literature. Moreover, when MgCO3·3H2O is supplied, the algae appear to form clusters, which favor their separation from the solution. Overall, this work analyzes the potential to combine two carbon dioxide (CO2) utilization options, i.e., mineral carbonation and microalgae cultivation, and it demonstrates the feasibility of the process. However, control of the pH and the carbon dosage is required to attain optimal biomass productivity.

Enhanced precipitation of magnesium carbonates using carbonic anhydrase

“…Precipitation experiments were carried out with a continuously stirred batch reactor (Series 5100 Glass Reactor, Parr Instrument, U.S.A.), which we employed in an earlier paper 31 and upgraded for this work. A schematic of the set-up is shown in Fig.…”

“…The growth medium used was BG-11, whose recipe is described in an earlier paper. 31 The culture was centrifuged and the pellet washed with ultrapurified water 5 times before the cells were added into the NaOH solution. This washing process removes all nutrients from the supernatant growth medium and avoid possible interference in the mineralization process.…”

“…Previous works show precipitation at similar conditions. 31,37 However, in those cases the reactor was slightly depressurized in order to inject the solution containing Mg 2+ . Depressurization, even for a few seconds, temporarily reduces the CO 2 concentration in the atmosphere leading to an increase in pH that may favor precipitation.…”

CO2 Utilization and Long-Term Storage in Useful Mineral Products by Carbonation of Alkaline Feedstocks

“…(2019) studied the heat effects and storage capacity for thermal energy storage applications of a composite materialmade by magnesium carbonate hydrate (Nesquehonite) and silica gel, where the former one is produced by carbonation of alkalinematerials with Mgbearing phases. Carbonation for production of metastable carbonates such as nesquehonite was also recently proposed and tested as carbon growth media for microalgae, for cases in which pure or even diluted CO 2 sources may not be available nearby algae production plants (Ye et al, 2019).…”

Review and Perspectives on CO2 Bubble Dynamic Characteristics in Different Liquids during Carbon Capture, Utilization, and Storage Process

“…To reduce the greenhouse effect, different countries around the world pay more attention to carbon capture, utilization, and storage (CCUS) technology. , CCUS technologies are used to capture and purify the CO 2 emitted in the production process and then invest in the new production process. CO 2 is recycled in the cycle, which is ecofriendly and economically maximized.…”